Core.



.lOllNN \VITTLIFl", F MINNEAPOLIS MINNESOTA.

CORE.

Specification of Letters Patent.

Patented March 23, 1909.

Application filed December 17, 190 8. SeriatNo. 468,065.

To all whom it may concern:

Be it knownthat LJOIINN TYITTLI F, acitizen of the United States,residing at Minneapolis, in the county of Hennepin and State ofMinnesota, have invented certain new and useful Improvements in Cores;and I do hereby declare the following to be a full, clear, and exactdescription of the invention, such as will enable others skilled in theart to which it appertains to make and use the same. 4 I

My invention has for its object to improve the art of making inolderscores, and it com-' prises" both-a new product and a process ofproducing thesame.

My improved cores are made from sand and glue, used approximately in theproportion of one part of glue to twenty-five of sand. i

The process of producing these improved cores is as follows: Dry sand isheated and the glue, while hot and in liquid form, is mixed with thisdry and hot sand. T he glue should be in such an amount, that it will beentirely taken up and held by the sand, and they should be so wellcommingled that there will be no dripping of the glue, and-- eachparticle of sand will he covered with glue. The sand thus treated isallowed to cool, and as it cools, there being no moisture present, thegrains of sand covered with the glue will separate and maintain granularform. When the cores are to be formed from this glue treated sand, wateris mixed therewith, or the material is otherwise moistened, so that itwill form an adhesive pliable mass capable of being molded into anydesired form. The properly formed core is then baked until it is hard.

The cores constructed as above described, when subject to the intenseheat of molten metal poured arouml the same, will become very brittle,so that by very slight agitation, they will rcturnto granular form, andhence, may he rattled out of casings through the usual openings providedtherefor. A core thus constructed however, ,when suhi ectcd to the hotmetal, will produce but very little, if any, gas, and hence, rents suchas usually found necessary, are not required. Furthermore, cores may bevery quickly and'rapidly sists; first, in connningling sand and glue;

second, in moistening the sand and glue and in forming the core out ofthis connnmgled sand and glue: and third, 1n baking the core.

made in accordance with my improved proc- 3. The process of producingcores, which consists; first, in commingling dry hot sand with hotliquid glue, and then drying the material to reduce the same to granularform; second, in moistening this glue coated sand and giving the samethe desired form; and third, in baking the core'thus formed.

In testimony whereof I affix my signature in presence of two- Witnesses.

JOHNX WITTLIFF. Witnesses H. D. KILGORE,

ALICE J. SWANSON.

